This blog discusses current weather, weather prediction, climate issues, and other topics

Wednesday, January 7, 2009

rain shadow moves north

As the computer models have been suggesting for a while, the rain shadow is slipping northward, bringing moderate rain into Seattle. The reason--the large scale flow approaching the Olympics has shifted from westerly to southwesterly...which results in the rain shadow moving northward.

35 comments:

Now maybe the "local" weather and news folks will have a reason to remember the other thousands of their customers. Seems the small numbers on the rain gauge in the Emerald City doesn't give them a flavor of what's REALLY happening outside all around them in the rest of western WA.

We're on the Middle Fork Snoqualmie...55 feet above it. Has it crested? I keep looking and the CFS seems to be hovering around 30,000 for the last few hours, It keeps going up or down 1000-2000 CFS, but is remaining pretty steady. We have had non-stop buckets since last night and our neighborhood has been cut off by mudslides on both access roads. Kids are sleeping over at friends. No power because of slides knocking down poles, but we've got a bottle of wine, the generator humming and the kerosene lamps lit.

Cliff, with respect, I disagree with your assertion that stimulus money would be well spent on a new weather station by the coast, but if you can show me how better forecasting would help put us on better economic footing, I might change my mind.

I will reiterate that we should not increase government spending on snow removal in Seattle given how rarely we actually need it. Way too many other pressing needs. Way too many. (I don't think most people realize yet how dire our economic circumstances are).

By the way, you request that bloggers not discuss "global warming or politics," but, as you yourself have abundantly demonstrated in your advocacy for government money for a weather station and for better snow removal, the weather IS political, after all!

I think those of us in south Snohomish county (Lynnwood/Edmonds) actually resent being protected by the Olympic rainshadow, as we were earlier today. We much more relish our role as a center for the convergence zone. Let it rain, baby!!

5:22pm --rain continuing to fall steadly here, and the rivers are risin...

Nearly 6" here in Maple Valley on lake wilderness in the last 24 hours. Both Neighbors docks are under water, mine is high and dry although the yard is getting smaller. A section of the railroad grade trail across the lake had succumbed to mass wasting this morning.

JewelyaZ asks "What will it take for them to redefine the "100-year flood" numbers? It seems we've had two or three 100-year floods in the past few years...."

My understanding is that the "100-year" designation refers to a one in hundred probability of something occurring in a given year. It is not as if once you have a "100-year flood" you can plan on not having one for the next 99 years. But it also seems clear that the entire "xx-year event" requires a very long-term weather record and assumes climate is not changing - the latter making the term rather useless with climate change our reality.

All, You can get two hundred-year storms back to back. Basically, a hundred year storm has a 1% of happening in a particular year. And remember, that is in the SAME location. So you have more chances for a big storm if you consider multiple locations. A major question is whether large storms are getting more frequent...I have a student working on this question right now.

Prof Mass, regarding 100 yr storm and the research....with all due respect, from your comments about climate/warming...i would suspect you already have the hypothesis that yes, the frequency of so called 100 yr or even major events is increasing.......so on those lines, would you consider that eiter we are more sissy about our weather endurance (the Jim Foreman effect...evertying is major), or that with more people, we are in more places and able to measure better...or other factors....or is it a done deal that your student will prove bigger and more storms?

Pouring, pouring, pouring in Lake Forest Park. It started raining heavily at about 4:30 pm and it's been continuing since then. What a change since it was completely dry at 1:30 when I walked my dog. Very gusty most of the day and now no real wind happening. It's about 52 degrees. What a drastic difference from two weeks ago.

gusting winds to 17mph and tons of water in east olympia. was just out on the point at hearthfire and it was difficult to see the shore at 3:30 but had settled a bit by 6:30. man i'm glad this wasn't snow...

Bah. It's been pouring continuously in North Bend for 1.5 days. The rivers have stabilized near their peaks, but my back yard is still filling and my house is starting to look like lakeside property.

We'd be fine if the rain lets up in the morning, but I just took a look at some of the models at:http://www.atmos.washington.edu/mm5rt/

It seems like they agree that a convergence zone is going to form out this way tomorrow afternoon. That might be enough to put us over the top, so to speak. Give me boring old cloudy with drizzle over 2 days of this any day.

I agree with nocurling.There is one thing that we can all be happy for, that this is all rain. I mean, yes, I am a snow LOVER. But I read one of Scott Sistek's comments on if this would of been snow, it would of been between 3-5 FEET of snow, if not more. I'm not sure about you all, but that right there, is something I am thankful we DIDN'T get (feels weird to say, since we have pretty much seen everything this winter).

Regarding Climate Change-Didn't want to go here but I have stayed still long enough..

I love all these arm-chair climatologist, especially the ones who claim anonymous. Interesting as well that the weak arguments presented here are backed by data inputs that are “stand alone” or doesn't take in all the other thousands of studies and variables( A Fox News procedure) that span the collective thinking of people who turned our hobbies into a highly skilled professions... Yes it is good to question science and the man behind the curtain, but if you want to get in the ring and play you better get beyond the gotcha studies.

@brian. having grown up in southern ontario, where they got 400+ cm of snow last year, this is easy to take. otoh, i feel for folks who are in low-lying areas where the flooding will have a devastating effect. my heart goes out to them.

Cliff, I am sure you already know this but at the beginning of the blog, not all the words are showing up so it makes it hard to read and figure out exactly all you are saying. But I sure do appreciate you doing the blog.

I have just been reading your book on floods(Chapter 3). Wow! This seems remininscent of last year and 1996. I had read that climate change would bring more precipitation to the northwest. I know you do not want this to a blog about climate change but I must ask, are we seeing a beginning of the prediction? Are there any data that would suggest such a trend? I know a couple of years do not provide sufficient data points but seeing more flooding here in Bellingham than I have seen in my 39 years here, I am very curious.

Also, I appreciated the photo in your book of the 1948 floods in Kennewick. I was there and I remember them.